Free Grade 9 Biology Worksheets with Answers

Grade 9 Cell Biology

Cell structure and the jobs of organelles such as the nucleus, cell membrane and mitochondria, plus plant vs animal cells.

e.g. What structure surrounds and supports a plant cell (that animal cells lack)?

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Grade 9 Biomolecules

HS-LS1-6

Carbohydrates, lipids, proteins and nucleic acids, and how enzymes work.

e.g. Which biomolecule forms most of the cell membrane?

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Grade 9 Cell Transport & Homeostasis

HS-LS1-3

Diffusion, osmosis and active transport, and how cells keep stable conditions.

e.g. A cell is placed in pure water. What happens to an animal cell?

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Grade 9 DNA, RNA & Protein Synthesis

HS-LS1-1

DNA structure, base pairing, transcription and translation — including writing complementary strands.

e.g. What is translation?

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Grade 9 Genetics Vocabulary

HS-LS3-1

Key genetics terms: gene, allele, dominant, recessive, genotype and phenotype.

e.g. Is the genotype Bb homozygous or heterozygous?

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Grade 9 Punnett Squares & Crosses

HS-LS3-3

Predicting offspring with Punnett squares and working out genotype and phenotype ratios.

e.g. Cross yy × Yy. What is the expected ratio of dominant to recessive phenotypes?

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Grade 9 Genetics Basics (Mixed)

HS-LS3-2

A mixed set on genetics vocabulary and Punnett square crosses.

e.g. What do we call an organism with two identical alleles for a trait?

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Grade 9 Natural Selection & Adaptation

HS-LS4-4

Variation, mutation and natural selection, and how populations change over generations.

e.g. What evidence supports evolution?

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Grade 9 Classification & Taxonomy

HS-LS4-1

Domains, kingdoms and scientific names, and how organisms are classified.

e.g. Put in order from broadest to most specific: species, kingdom, genus, family

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Grade 9 Population Ecology

HS-LS2-1

Population growth, limiting factors, carrying capacity and biodiversity.

e.g. What is carrying capacity?

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Grade 9 Producers, Consumers & Decomposers

HS-LS2-4

Producers, consumers and decomposers, and how energy and nutrients flow through an ecosystem.

e.g. What is a secondary consumer?

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Grade 9 Biomes & Symbiosis

HS-LS2-6

Biomes and the relationships between species: mutualism, commensalism, parasitism and predation.

e.g. What is it called when one organism benefits and the other is harmed?

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Grade 9 Ecosystems (Mixed)

A mixed set on the roles living things play in an ecosystem, biomes and symbiosis.

e.g. What do we call an organism that breaks down dead material for nutrients?

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Grade 9 Photosynthesis & Respiration

AdvancedHS-LS1-5

Photosynthesis and cellular respiration: their inputs, outputs and where each takes place in the cell.

e.g. What gas do plants release as a byproduct of photosynthesis?

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Grade 9 Mitosis & Meiosis

AdvancedHS-LS1-4

The stages of mitosis and meiosis and how the two kinds of cell division differ.

e.g. During which phase of mitosis are sister chromatids pulled apart?

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Grade 9 Challenge: Think Like a Scientist

Challenge

Surprising questions and thought experiments that test real scientific reasoning.

e.g. Why is the sky blue?

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